Nitrosamines Analysis in Water - Using Triple Quadrupole GC/MS/MS: Consumables workflow ordering guide

Significance of the topic

Safe drinking water is critical for public health. Nitrosamines, particularly N-nitrosodimethylamine (NDMA), are highly potent DNA-damaging byproducts formed when nitrogenous precursors react with disinfectants such as chlorine or chloramine. Regulatory bodies recognize their carcinogenic risks, with the WHO guideline value for NDMA set at 100 ng/L and some regions, such as California, adopting a stricter goal of 3 ng/L to limit lifetime cancer risk to one in a million.

Objectives and study overview

This summary reviews the application of EEA-Agilent Method 521.1 for the quantitation of nitrosamines in drinking water using triple quadrupole GC/MS/MS. The aim is to demonstrate method equivalence to EPA Method 521, highlighting improvements in sensitivity, run time, and chromatographic performance across multiple inlet configurations.

Methodology and instrumentation

The method employs liquid-liquid extraction of water samples spiked with internal standards followed by analysis on a triple quadrupole GC/MS/MS system in multiple reaction monitoring (MRM) mode. Three inlet liner and injection conditions were evaluated: splitless injections at 35 °C ramping to 280 °C, and splitless or pulsed splitless modes at 260–280 °C with ultra-inert liners. Calibration standards ranged from low ng/L levels to meet the lowest concentration minimum reporting level (LCMRL) requirements.

Used Instrumentation

• Agilent 7010 and 7000 series triple quadrupole GC/MS systems
• Agilent J&W DB-1701 GC column (30 m × 0.25 mm, 1.0 µm film)
• Ultra-inert splitless inlet liners (2 mm dimpled or 4 mm double-tapered)
• Multiple inlet septa, ferrules, and syringes for sample introduction

Key results and discussion

All three inlet configurations achieved detection limits and reporting levels below regulatory thresholds. Calibration curve linearity coefficients (R2) exceeded 0.993 for eight target nitrosamines under each condition, demonstrating robust quantitation. The GC/TQ approach yielded faster run times and improved baseline separation compared to ion trap systems while reducing injection volumes.

Benefits and practical applications

• Enhanced sensitivity enables detection of nitrosamines at sub-ng/L levels
• Shorter analysis cycles improve throughput for routine monitoring
• Flexibility in inlet configuration allows method adaptation to existing laboratory setups
• Alignment with international guidelines supports regulatory compliance and risk assessment

Future trends and possibilities

Advancements in automated sample preparation and high-throughput workflows will further streamline nitrosamine testing. Emerging MS technologies, such as microfluidic GC and ambient ionization, promise on-site screening capabilities. Integration of artificial intelligence for data processing may enhance analyte identification and trend detection in large datasets.

Conclusion

EEA-Agilent Method 521.1 on triple quadrupole GC/MS/MS provides a fast, sensitive, and robust workflow for the determination of nitrosamines in drinking water. The method consistently meets or exceeds regulatory criteria across multiple inlet conditions, supporting reliable monitoring and public health protection.

Reference

1. Environmental Working Group. Tap Water Database Reviewed Nitrosamines. 2020.
2. World Health Organization. N-Nitrosodimethylamine in Drinking-water: Background Document for Development of Guidelines for Drinking-water Quality. 2008.
3. Australian Government National Health and Medical Research Council. Australian Drinking Water Guidelines 6, Version 3.5. 2011.
4. US EPA. Letter of Equivalency for EEA-Agilent 521.1 for the Analysis of Nitrosamines in Drinking Water by GC/MS/MS. March 13, 2018.
5. Agilent Technologies. Nitrosamines Analysis in Drinking Water Using GC/MS/MS: Meeting Equivalence to EPA Method 521. Publication 5991-9224EN.